Method, terminal, and base station for use in data transmission

ABSTRACT

Disclosed are a method, a terminal, and a base station for use in data transmission. The present invention allows the terminal to receive a downlink control signaling at a low frequency band and to transmit data at a high frequency band when high-speed data transmission is required. The method comprises: when there is no data transmission, the terminal receives first indication information in a first cell using a first frequency band, the first indication information being used for indicating a terminal having received the first indication information to use a second frequency band for data transmission; the terminal transmits data in a second cell using the second frequency band on the basis of the first indication information when data transmission is required.

TECHNICAL FIELD

The disclosure relates to the field of communications, and moreparticularly to a data transmission method, a terminal and a basestation.

BACKGROUND

Along with constant increase of requirements on data transmission rate,communication quality and the like of mobile communication,high-frequency-band broadband is introduced into wireless communication.A terminal may receive downlink control signaling such as systeminformation or paging information through a low-frequency-bandnarrow-band cell and perform high-speed data transmission through ahigh-frequency-band broadband cell.

At present, there is such a known technology that, for solving theproblem of relatively high received power consumption caused by the factthat a terminal in an idle state receives downlink signaling through ahigh-frequency-band broadband link, the terminal may reside in alow-frequency-band narrow-band cell, enter the idle state and receivesystem information and paging information in a low band. When theterminal has uplink data to be transmitted, the terminal may access ahigh-frequency-band broadband cell for high-speed data transmission.

However, a terminal has to perform a cell access process before theterminal can perform high-speed data transmission through ahigh-frequency-band broadband cell. Therefore, the process forinitiating high-speed data transmission takes a relatively long time andhas a relatively high signaling overhead.

SUMMARY

The disclosure provides a data transmission method and device, to enablea terminal to keep synchronized with both a low-frequency-band cell anda high-frequency-band cell, receive downlink control signalingtransmitted by the low-frequency-band cell and, when high-speed datatransmission is required, access the high-frequency-band cell as fast aspossible or perform data transmission with the high-frequency-band cell,thereby reducing process and signaling overhead of a high-speed dataservice.

According to a first aspect, the disclosure provides a data transmissionmethod, which may include that, when no data is to be transmitted orreceived, a terminal receives first indication information in a firstcell using a first frequency band, the first indication informationbeing configured to instruct the terminal receiving the first indicationinformation to perform data transmission using a second frequency bandwhen there is data to be transmitted or received; and when there is datato be transmitted or received, the terminal performs data transmissionin a second cell using the second frequency band according to the firstindication information.

When the terminal is in an idle state, or context of the terminal isstill maintained at a previous serving base station but mobilitymanagement of the terminal may be implemented under a cell selection orcell reselection rule, it may be understood that the terminal is in ano-data-transmission state. In other words, mobility of the terminal isnot directly controlled by a network.

The terminal completes synchronization with a target cell in advance onthe first frequency band and, when there is data to be transmitted orreceived, performs data transmission with the target cell, so thatrelatively high power consumption probably brought by reception ofdownlink control signaling by the terminal camping on a high frequencyband is avoided. Meanwhile, synchronization with the target cell iscompleted in advance to make it possible to implement data transmissionwith the target cell when there is data to be transmitted or received.Compared with the prior art, the method greatly reduces cell accessprocess in the prior art and reduces a signaling overhead.

In combination with the first aspect, in a first possible implementationmode of the first aspect, the operation that the terminal performs datatransmission in the second cell using the second frequency bandaccording to the first indication information when there is data to betransmitted or received may include that, the terminal determines one ormore second cells using the second frequency band as (a) target cell(s)according to the first indication information; the terminal performscell synchronization with the target cell(s); and when there is data tobe transmitted or received, the terminal uses the second frequency bandfor data transmission with the target cell(s).

The terminal determines the one or more second cells to be the targetcell(s) according to the cell selection or cell reselection rule andperforms data transmission with the target cell(s).

In combination with the first aspect or the abovementioned possibleimplementation mode thereof, in a second possible implementation mode ofthe first aspect, the first indication information may be paginginformation transmitted by a first base station through the first cell,or the first indication information may be the paging information andconfiguration information of the target cell(s), the first indicationinformation may include information of a second frequency band and/orinformation of a base station containing the target cell(s) and/orinformation of the target cell, the first base station may be a basestation containing the first cell. The operation that the terminaldetermines the one or more second cells using the second frequency bandto be the target cell(s) according to the first indication informationmay include that, the terminal determines the target cell(s) accordingto the paging information; or the terminal determines the target cell(s)according to the paging information and the configuration information ofthe target cell(s).

When there is downlink data to be transmitted, the first base stationmay indicate the information of the second frequency band and/orinformation of the base station containing the target cell(s) and/orinformation of the target cell for data transmission required by theterminal through the paging information. Or, the first base station mayalso indicate the information of the second frequency band and/orinformation of the base station containing the target cell(s) and/orinformation of the target cell for data transmission required by theterminal through the paging information and the configurationinformation of the target cell(s). Therefore, the terminal may look forthe target cell(s) in a smaller range and the efficiency of determiningthe target cell may be improved.

In combination with the first aspect or the abovementioned possibleimplementation modes thereof, in a third possible implementation mode ofthe first aspect, the first indication information may be systeminformation of the second cell transmitted by the first base stationthrough the first cell, the system information of the second cell mayinclude information of the frequency band of the second cell and/orinformation of the base station (i.e., second base station) containingthe second cell and/or information of the second cell, the first basestation may be the base station containing the first cell. The operationthat the terminal receives the first indication information in the firstcell using the first frequency band when no data is to be transmitted orreceived may include that, the terminal receives system information ofat least one second cell in the first cell using the first frequencyband, the system information of the at least one second cellcorresponding to the at least one second cell. The operation that theterminal determines the one or more second cells using the secondfrequency band to be the target cell(s) according to the firstindication information may include that, the terminal determines one ormore second cells from the at least one second cell to be the targetcell(s) according to the system information of the at least one secondcell.

When there is uplink data to be transmitted, the terminal may determinethe target cell(s) for uplink data transmission through the informationof the frequency band of the second cell and/or information of the basestation containing the second cell and/or information of the second cellindicated by the system information and under the cell selection or cellreselection rule.

In combination with the first aspect or the abovementioned possibleimplementation modes thereof, in a fourth possible implementation modeof the first aspect, the operation that the terminal performs cellsynchronization with the target cell(s) may include that, the terminaltransmits an uplink synchronization request to a target base stationcontaining the target cell(s) on the second frequency band, the uplinksynchronization request is configured to obtain uplink synchronizationinformation of the terminal and the target cell(s); the terminalreceives the uplink synchronization information in the first cell, theuplink synchronization information is acquired by the first base stationfrom the target base station, the uplink synchronization information isdetermined by the target base station on the basis of the uplinksynchronization request and the first base station is the base stationcontaining the first cell; and the terminal performs uplinksynchronization with the target cell(s) according to the uplinksynchronization information.

The terminal may transmit the uplink synchronization request on thesecond frequency band indicated by the first indication information toacquire the uplink synchronization information between the targetcell(s) and the terminal and perform uplink synchronization with thetarget cell(s).

In combination with the first aspect or the abovementioned possibleimplementation modes thereof, in a fifth possible implementation mode ofthe first aspect, the operation that the terminal performs cellsynchronization with the target cell(s) may include that, the terminalreceives downlink synchronization information of the first cell in thefirst cell; the terminal determines downlink synchronization informationof the target cell(s); and the terminal performs downlinksynchronization with the target cell(s) according to the downlinksynchronization information of the target cell(s).

In combination with the first aspect or the abovementioned possibleimplementation modes thereof, in a sixth possible implementation mode ofthe first aspect, the operation that the terminal determines thedownlink synchronization information of the target cell(s) may includethat, the terminal receives at least one downlink synchronization offsetinformation transmitted by the first base station through the first celland corresponding to the at least one second cell, each downlinksynchronization offset information including a time offset betweentiming of the corresponding second cell and timing of the first cell andthe first base station being the base station containing the first cell;and the terminal determines the downlink synchronization information ofthe target cell(s) according to the downlink synchronization offsetinformation of the at least one second cell.

The terminal may acquire the downlink synchronization information of thefirst cell and the downlink synchronization information of the targetcell(s) from the first base station for downlink synchronization withthe target cell(s).

According to a second aspect, the disclosure provides a datatransmission method, which may include that, a first base stationdetermines first indication information. The first indicationinformation is configured to instruct a terminal receiving the firstindication information to transmit data in a second cell using a secondfrequency band, and the first base station is a base station to which afirst cell using a first frequency band belongs; and the first basestation transmits the first indication information through the firstcell.

The terminal completes synchronization with a target cell in advance onthe first frequency band and, when there is data to be transmitted orreceived, performs data transmission with the target cell, so thatrelatively high power consumption probably brought by reception ofdownlink control signaling by the terminal camping on a high frequencyband is avoided. Meanwhile, synchronization with the target cell iscompleted in advance to make it possible to implement data transmissionwith the target cell when there is data to be transmitted or received.Compared with the prior art, the method greatly reduces cell accessprocess in the prior art and reduces a signaling overhead.

In combination with the second aspect, in a first possibleimplementation mode of the second aspect, the first indicationinformation may be paging information, or the first indicationinformation may be the paging information and configuration informationof a target cell, the first indication information may includeinformation of a second frequency band and/or information of a targetbase station and/or information of the target cell, the second cell mayinclude the target cell, a target base station may be a base stationcontaining the target cell, and the operation that the first basestation transmits the first indication information through the firstcell may include that, the first base station transmits the paginginformation through the first cell; or the first base station transmitsthe paging information and the configuration information of the targetcell through the first cell.

When there is downlink data to be transmitted, the first base stationmay indicate the information of the second frequency band and/orinformation of the target base station and/or information of the targetcell for data transmission required by the terminal through the paginginformation.

In combination with the second aspect or the abovementionedimplementation mode thereof, in a second possible implementation mode ofthe second aspect, the first indication information may be systeminformation of the second cell, the system information of the secondcell may include the information of the frequency band of the secondcell and/or information of the base station containing the second celland/or information of the second cell, and the operation that the firstbase station transmits the first indication information through thefirst cell may include that, the first base station receives systeminformation of at least one second cell transmitted by at least onesecond base station, the system information of the at least one secondcell corresponds to the at least one second cell; and the first basestation transmits the system information of the at least one second cellthrough the first cell.

When there is uplink data to be transmitted, the terminal may determinethe target cell for uplink data transmission through the information ofthe second frequency band and/or information of the second base stationand/or information of the second cell indicated by the systeminformation and through a cell selection or cell reselection rule.

In combination with the second aspect or the abovementionedimplementation modes thereof, in a third possible implementation mode ofthe second aspect, the method may further include that, the first basestation transmits uplink synchronization information through the firstcell, the uplink synchronization information is acquired by the firstbase station from the target base station and the uplink synchronizationinformation is determined by the target base station on the basis of anuplink synchronization request transmitted by the terminal to the targetbase station on the second frequency band, the target base station maybe the base station containing the target cell, and the target cell maybe determined by the terminal from the at least one second cell.

The terminal may transmit the uplink synchronization request on thesecond frequency band indicated by the first indication information toacquire the uplink synchronization information between the target celland the terminal and perform uplink synchronization with the targetcell.

In combination with the second aspect or the abovementionedimplementation modes thereof, in a fourth possible implementation modeof the second aspect, the method may further include that, the firstbase station transmits downlink synchronization information of the firstcell to the terminal through the first cell.

In combination with the second aspect or the abovementionedimplementation modes thereof, in a fifth possible implementation mode ofthe second aspect, the method may further include that, the first basestation transmits at least one downlink synchronization offsetinformation corresponding to the at least one second cell to theterminal through the first cell, each downlink synchronization offsetinformation includes a time offset between timing of the correspondingsecond cell and timing of the first cell.

The terminal may acquire the downlink synchronization information of thefirst cell and downlink synchronization information of the target cellfrom the first base station for downlink synchronization with the targetcell.

According to a third aspect, the disclosure provides a data transmissionmethod, which may include that, a second base station transmits systeminformation of a second cell to a first base station, the systeminformation is configured to indicate a system parameter of the secondcell, a carrier frequency corresponding to the second cell belongs to asecond frequency band, the first base station is a base stationcontaining a first cell using a first frequency band and the second basestation pre-stores a mapping relationship between the second cell andthe first cell; and the second base station transmits data with aterminal through the second cell.

In combination with the third aspect, in a first possible implementationmode of the third aspect, the method may further include that, thesecond base station receives an uplink synchronization requesttransmitted by the terminal on the second frequency band, the uplinksynchronization request is configured to obtain uplink synchronizationinformation of the terminal and the second cell; and the second basestation determines the uplink synchronization information according tothe uplink synchronization request, and transmits the uplinksynchronization information to the first base station.

The second base station may transmit the uplink synchronizationinformation to the terminal through the uplink synchronization requestreceived from the terminal on the second frequency band to facilitateuplink synchronization between the second base station and the terminal.

According to a fourth aspect, the disclosure provides a terminal, whichis configured to execute the method in the first aspect or any possibleimplementation mode of the first aspect. Specifically, the terminalincludes units configured to execute the method in the first aspect orany possible implementation mode of the first aspect.

According to a fifth aspect, the disclosure provides a base station,which is configured to execute the method in the second aspect or anypossible implementation mode of the second aspect. Specifically, thebase station includes units configured to execute the method in thesecond aspect or any possible implementation mode of the second aspect.

According to a sixth aspect, the disclosure provides another basestation, which is configured to execute the method in the third aspector any possible implementation mode of the third aspect. Specifically,the base station includes units configured to execute the method in thethird aspect or any possible implementation mode of the third aspect.

According to a seventh aspect, the disclosure provides a terminal, whichincludes a transceiver, a processor, a memory and a bus system, thetransceiver, the memory and the processor are connected through the bussystem, the memory is configured to store instructions, the processor isconfigured to execute the instructions stored in the memory to controlthe transceiver to transmit and receive signals, and when the processorexecutes the instructions stored in the memory, such execution enablesthe processor to execute the method in the first aspect or any possibleimplementation mode of the first aspect.

According to an eighth aspect, the disclosure provides a base station,which includes a transceiver, a memory, a processor and a bus system,the transceiver, the memory and the processor are connected through thebus system, the memory is configured to store instructions, theprocessor is configured to execute the instruction stored in the memoryto control the transceiver to transmit and receive signals, and when theprocessor executes the instructions stored in the memory, such executionenables the processor to execute the method in the second aspect or anypossible implementation mode of the second aspect.

According to a ninth aspect, the disclosure provides another basestation, which includes a transceiver, a memory, a processor and a bussystem, the transceiver, the memory and the processor are connectedthrough the bus system, the memory is configured to store instructions,the processor is configured to execute the instructions stored in thememory to control the transceiver to transmit and receive signals, andwhen the processor executes the instructions stored in the memory, suchexecution enables the processor to execute the method in the thirdaspect or any possible implementation mode of the third aspect.

According to a tenth aspect, the disclosure provides a computer-readablemedium, which is configured to store a computer program, the computerprogram including instructions configured to execute the method in thefirst aspect or any possible implementation mode of the first aspect.

According to an eleventh aspect, the disclosure provides acomputer-readable medium, which is configured to store a computerprogram, the computer program including an instruction configured toexecute the method in the second aspect or any possible implementationmode of the second aspect.

According to a twelfth aspect, the disclosure provides acomputer-readable medium, which is configured to store a computerprogram, the computer program including instructions configured toexecute the method in the third aspect or any possible implementationmode of the third aspect.

In some implementation modes, the paging information includes the secondfrequency band information and/or the corresponding base station (i.e.,target base station) information of the target cell and/or the targetcell information, and the first base station is the base stationcontaining the first cell.

In some implementation modes, the second frequency band informationincludes at least one of frequency band information, a bandwidth, athreshold value or an offset. The corresponding base station informationof the target cell includes a target base station Identifier (ID). Thetarget cell information includes at least one of a cell ID or a cellaccess technology.

In some implementation modes, the system information of the second cellincludes the frequency band information of the second cell and/or thecorresponding base station information of the second cell and/or thesecond cell information.

In some implementation modes, the second frequency band informationincludes at least one of the frequency band information, the bandwidth,the threshold value or the offset. The corresponding base stationinformation of the second cell includes a second base station ID. Thesecond cell information includes at least one of a cell ID or a cellaccess technology.

In some implementation modes, the uplink synchronization request and atransmitting resource are determined by the target base station andtransmitted to the terminal through the first base station. Or, uplinksynchronization request information is transmitted to the terminal bythe first base station after the first base station requests the targetbase station and the target base station acknowledges the uplinksynchronization request and allocates the transmitting resource. Theuplink synchronization request information includes indicationinformation of the transmitting resource.

According to the data transmission method, terminal and base stationprovided in the disclosure, the terminal may receive downlink controlsignaling on a low frequency band and, when high-speed data transmissionis required, access a high-frequency-band cell as fast as possible orperform data transmission with the high-frequency-band cell, therebyreducing process and signaling overhead of a high-speed data service.

BRIEF DESCRIPTION OF DRAWINGS

In order to describe the technical solutions of the embodiments of thedisclosure more clearly, the drawings required to be used in theembodiments of the disclosure will be simply introduced below. It isapparent that the drawings described below are only some embodiments ofthe disclosure. Other drawings may further be obtained by those ofordinary skill in the art according to these drawings without creativework.

FIG. 1 illustrates a schematic diagram of an application scenarioaccording to an embodiment of the disclosure.

FIG. 2 illustrates a schematic flowchart of a data transmission methodaccording to an embodiment of the disclosure.

FIG. 3 illustrates a schematic block diagram of a terminal according toan embodiment of the application.

FIG. 4 illustrates a schematic block diagram of a base station accordingto an embodiment of the application.

FIG. 5 illustrates a schematic block diagram of another base stationaccording to another embodiment of the application.

FIG. 6 illustrates another schematic block diagram of a terminalaccording to an embodiment of the application.

FIG. 7 illustrates another schematic block diagram of a base stationaccording to an embodiment of the application.

FIG. 8 illustrates another schematic block diagram of another basestation according to an embodiment of the application.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the disclosure will beclearly and completely described below in combination with the drawingsin the embodiments of the disclosure. It is apparent that the describedembodiments are not all embodiments but part of embodiments of thedisclosure. All other embodiments obtained by those of ordinary skill inthe art on the basis of the embodiments in the disclosure withoutcreative work shall fall within the scope of protection of thedisclosure.

It is to be understood that the technical solutions of the disclosuremay be applied to various communication systems, for example, a GlobalSystem of Mobile Communication (GSM), a Code Division Multiple Access(CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system,a General Packet Radio Service (GPRS), a Long Term Evolution (LTE)system, an Advanced Long Term Evolution (LTE-A) system and a UniversalMobile Telecommunication System (UMTS).

It is also to be understood that, in the embodiments of the disclosure,User Device (UE includes, but not limited to, a Mobile Station (MS), amobile terminal, a mobile telephone, a handset, a fixed station, a fixedterminal, portable device and the like. The UE may communicate with oneor more core networks through a Radio Access Network (RAN). For example,the UE may be a mobile telephone (or called a “cell” phone), a computerwith a wireless communication function and the like. The UE may also bea portable, pocket, handheld, computer-embedded, instrument-embedded orvehicle-mounted device.

FIG. 1 illustrates a schematic diagram of an application scenarioaccording to an embodiment of the disclosure. FIG. 1 illustrates ahigh/low-frequency hybrid networking system, which includes alow-frequency base station 11, at least one high-frequency base station12 and a terminal 13.

In the embodiment of the disclosure, a frequency band of thelow-frequency base station 11 is lower than a frequency band of thehigh-frequency base station 12. The frequency band adopted for thelow-frequency base station 11 may be a low frequency band below 6 GHz,for example, 2 GHz and 5 GHz. The frequency band adopted for thehigh-frequency base station 12 may be a millimeter frequency band(namely above 6 GHz) as a representative of a high frequency band. Forexample, the frequency used for the high-frequency base station 12 maybe 72 GHz, 28 GHz or 14 GHz.

The low-frequency base station 11 covers a relatively large region. Thehigh-frequency base station 12 implements hot spot coverage within thecoverage of the low-frequency base station, to improve capacity of a hotregion. The terminal 13 is usually configured with both a low-frequencytransceiver and a high-frequency transceiver. The low-frequencytransceiver is configured for data communication with the low-frequencybase station 11. The high-frequency transceiver is configured for datacommunication with the high-frequency base station 12.

The terminal 13 may camp in a low-frequency cell and receive downlinkcontrol signaling from the low-frequency base station 11. The downlinkcontrol signaling may include downlink control signaling, for example,system information and paging information, of the low-frequency cell anda high-frequency cell. Meanwhile, the terminal may transmit data withthe high-frequency base station 12 on the basis of the systeminformation and paging information of the high-frequency cell receivedfrom the low-frequency base station 11.

It is to be understood that the terms “low frequency” and “highfrequency” are only adopted to distinguish different frequency bands towhich carrier frequencies corresponding to the cells belong. The carrierfrequency of the low-frequency cell belongs to a low frequency band andthe carrier frequency corresponding to the high-frequency cell belongsto a high frequency band. The low-frequency base station is a basestation of the low-frequency cell and the high-frequency base station isa base station of the high-frequency cell. That is, for the basestations, a difference between low frequency and high frequency lies inthat carriers used by the base stations are located on differentfrequency bands. Therefore, the low-frequency base station and thehigh-frequency base station may be the same base station which uses thecarrier frequency of the low frequency band for data transmission andreception in the low-frequency cell and uses the carrier frequency ofthe high frequency band for data transmission and reception in thehigh-frequency cell. Or, the low-frequency base station and thehigh-frequency base station may be different base stations, thelow-frequency base station uses the carrier frequency of the lowfrequency band for data transmission and reception and thehigh-frequency base station uses the carrier frequency of the highfrequency band for data transmission and reception. There are no speciallimits made thereto in the disclosure.

In the embodiment of the disclosure, for convenience of distinction anddescription, the low-frequency base station may be denoted as a firstbase station, the low-frequency cell is denoted as a first cell, thehigh-frequency base station is denoted as a second base station and thehigh-frequency cell is denoted as a second cell. At least one secondcell may be configured within the coverage of the first base station ofthe first cell. Each cell may correspond to a serving base station. Or,multiple second cells may share the same serving base station (i.e., thesecond base station).

It is to be understood that “first” and “second” are adopted only todistinguish low frequency and high frequency and should not form anylimit to the disclosure. For example, the high-frequency base stationmay be denoted as the first base station, the high-frequency cell may bedenoted as the first cell, the low-frequency base station may be denotedas the second base station and the low-frequency cell may be denoted asthe second cell. It is also to be understood'that the first base stationand the second base station may be different base stations or may be thesame base station.

In the embodiment of the disclosure, the terminal, after determining totransmit data on a second frequency band, may receive system informationtransmitted by each of the at least one second cell on the secondfrequency band. The terminal determines a cell for data transmissionwith the terminal from the at least one second cell according to a cellselection or cell reselection rule. For convenience of distinction anddescription, the cell determined by the terminal is denoted as a targetcell and a serving cell of the target cell is denoted as a target basestation. It is to be understood that both the target base station andthe second base station may be high-frequency base stations and theterms “target base station” and “second base station” are only adoptedto distinguish whether they are base stations configured for datatransmission with the terminal. The target base station is relative. Forexample, for a terminal A, a base station A may be a target basestation; and for a terminal B, a base station B may be a target basestation.

It is to be understood that the target cell may share the same servingbase station with another cell in the at least one second cell. Thetarget cell may also share the same serving base station (i.e., thefirst base station) with the first cell. The target base station mayalso be the serving base station of the target cell only. There are nospecial limits made to a mapping relationship between a base station anda cell in the disclosure.

It is also to be understood that, in the following embodiments of thedisclosure, the first base station is a base station containing thefirst cell, the second base station is a base station to which thesecond cell belongs and the target base station is a base stationcontaining the target cell. However, the first base station, the secondbase station and the target base station are not limited and they mayalso be base stations containing other cells. In the embodiment of thedisclosure, exemplary descriptions will be made only with the conditionthat the first base station transmits information through the firstcell, the second base station transmits information through the secondcell and the target base station transmits information through thetarget cell as an example and should not form any limit to thedisclosure. For example, the first base station may also transmitinformation through another cell. There are no special limits madethereto in the disclosure.

For convenience of understanding and description, a data transmissionmethod according to the embodiments of the disclosure will be describedbelow in combination with FIG. 2 in detail with the condition that thefirst base station and the second base station are different basestations as an example. It is to be understood that the condition thatthe first base station and the second base station are different basestations is only for exemplary descriptions and should not form anylimit to the disclosure. When the first base station and the second basestation are the same base station, data transmission between theterminal and the high-frequency base station may still be implemented byexecuting the method 200.

FIG. 2 illustrates a schematic flowchart of a data transmission method200 according to an embodiment of the disclosure. It is to be understoodthat FIG. 2 illustrates detailed communication actions or operations ofthe data transmission method described from the view of interactionamong a terminal, a low-frequency base station (for example, a firstbase station) and a high-frequency base station (for example, a targetbase station) according to an embodiment of the disclosure. However,these actions or operations are only examples and other operations ortransformations of various operations in FIG. 2 may also be executed inthe embodiment of the disclosure. In addition, each action in FIG. 2 maybe executed in a sequence different from that presented in FIG. 2 andnot all the operations in FIG. 2 may be executed.

It is to be understood that the schematic flowchart of interaction amongthe terminal, the first base station and the second base station in FIG.2 is only exemplarily described and should not form any limit to thedisclosure. In the embodiment of the disclosure, the first base station(i.e., an example of the low-frequency base station) may form a mappingrelationship with at least one high-frequency base station (for example,including a second base station). That is, the terminal camping in thelow-frequency cell may transmit data with the at least onehigh-frequency base station.

As illustrated in FIG. 2, the method 200 includes the following actions.

In S202, when no data is to be transmitted or received, a terminalreceives first indication information in a first cell using a firstfrequency band.

Specifically, when a terminal is in an idle state, or when context ofthe terminal is still maintained at a previous serving base station butthe terminal may perform mobility management under a cell selection orcell reselection rule, it may be understood that the terminal is in ano-data-transmission state. In other words, mobility of the terminal isnot directly controlled by a network.

Here, the previous serving base station may be the first base station inthe embodiment of the disclosure or may be another base station. Thereare no special limits made thereto in the disclosure.

It is to be noted that the first cell does not specifically mean aspecific cell and the first cell may be a certain cell in a type ofcells transmitting the first indication information.

Specifically, a zone to be covered is divided into a plurality ofregions, an access point is set in each region to serve users in theregion, and the region is a cell. The definition of the cell may followthe existing concept of the cell, or may be one or more adjacent beamsin beam forming, or may be a carrier in the region.

In the embodiment of the disclosure, the first base station transmitsthe first indication information through the first cell (or on the firstfrequency band). The first indication information instructs the terminalto transmit data on a second frequency band. The terminal receiving thefirst indication information may transmit data in the second cell usingthe second frequency band according to the first indication information.

It is to be noted that the second cell does not specifically mean aspecific cell. Instead, the second cell may be a certain cell in cellsusing the second frequency band indicated by the first indicationinformation, or may be a cell indicated by the first indicationinformation. Specifically, the cell may be an existing cell, or may beone or more adjacent beams in beam forming, or may be a carrier in theregion.

It is to be understood that “first” and “second” are adopted only fordistinction and should not form any limit to the disclosure. It is alsoto be understood that the first base station is a base stationcontaining the first cell, or the first base station is a serving basestation of the first cell. The second base station is a base station towhich the second cell belongs, or the second base station is a servingbase station of the second cell. The first base station may correspondto a cell, i.e., the first cell, and may also be a serving base stationof multiple cells. The second base station may correspond to a cell,i.e., the second cell, and may also be a serving base station ofmultiple cells. There are no special limits made in the disclosure.

In the embodiment of the disclosure, the first base station is anexample of a low-frequency base station and may cover a relatively largeregion. The second base station is an example of a high-frequency basestation and may implement hot spot coverage in coverage of the firstbase station. That is, there may be one or more second cells in thefirst cell. As a serving base station of the second cell, a mappingrelationship with the low-frequency base station may be pre-stored ineach high-frequency base station. Or, each high-frequency base stationmay pre-store the mapping relationship with the low-frequency basestation and coverage of the high-frequency base station is within thecoverage of the low-frequency base station. Each high-frequency basestation may periodically transmit system information or paginginformation of the high-frequency cell served by the high-frequency basestation to the corresponding low-frequency base station according to themapping relationship.

In other words, the second base station within the coverage of the firstbase station forms the mapping relationship with the first base stationand each second base station in at least one second base station withinthe coverage of the first base station may transmit the systeminformation or paging information of the corresponding cell to the firstbase station through an interface between the base stations.Specifically, the system information or paging information of the secondcell may be periodically broadcast, and may be acquired by the firstbase station from the second base station through an X2 interface or aninterface with a function as same as or similar to that of the X2interface.

For example, a base station A (i.e., an example of the second basestation) within the coverage of the first base station may transmitsystem information or paging information of a cell A (i.e., an exampleof the second cell) to the first base station through an interfacebetween the base station A and the first base station. A base station B(i.e., another example of the second base station) within the coverageof the first base station may transmit system information or paginginformation of a cell B (i.e., another example of the second cell) tothe first base station through an interface between the base station Band the first base station.

It is to be understood that the X2 interface between the base stationsis listed above only for exemplary description, and should not form anylimit to the disclosure. Communication between the base stations throughthe interface with the function as same as or similar to that of the X2interface should not be excluded in the disclosure.

It is also to be understood that the method by which the second basestation transmits the system information or paging information of thesecond cell to the first base station through the interface between thebase stations is listed above only as a possible implementation modeabout that the first base station acquire the system information or thepaging system, and should not form any limit to the disclosure. Forexample, the first base station may also pre-configure the systeminformation and paging information of the second cell for periodicbroadcast in the first cell.

It is to be noted that the terminal, when being located within thecoverage of the first base station, may receive a downlinksynchronization signal (denoted as a first downlink synchronizationsignal for convenience of distinction and description) of the first basestation in the first cell (or on the first frequency band) for downlinksynchronization with the first cell and, after downlink synchronizationwith the first cell, camp in the first cell. In this case, the terminalmay receive downlink control signaling (for example, the systeminformation and the paging information) broadcast by the first basestation. It is to be understood that a method by which the terminalperforms downlink synchronization with the first cell on the firstfrequency band is similar to the prior art and will not be elaboratedherein for simplicity.

Or, when the first base station is a previous serving base station ofthe terminal, context of the terminal is still maintained at the firstbase station and the downlink control signaling transmitted by the firstbase station may be received on the first frequency band.

Without loss of generality, the first base station, after determiningthe second frequency band, may transmit the first indication informationin the first cell in a broadcast form, the first indication informationbeing configured to instruct terminals (including the abovementionedterminal) within the coverage of the first cell or the terminalreceiving the first indication information to transmit data with thesecond cell using the second frequency band. It is to be understood thatthere are multiple terminals in the coverage of the first cell and eachterminal, after receiving the first indication information broadcast bythe first base station through the first cell, may determine a targetcell for respective data transmission and perform cell synchronizationand data transmission with the respective target cell. The terminalmentioned above does not specifically mean a specific terminal, and theterminal may be a certain terminal receiving the first indicationinformation in a type of cells.

In S204, the terminal determines one or more second cells using thesecond frequency band as (a) target cell(s) according to the firstindication information.

In the embodiment of the disclosure, the at least one second cellincludes the target cell(s) and the system information includes systeminformation of the target cell(s). If there is only one second cell inthe coverage of the first base station, the terminal may directlydetermine the second cell to be the target cell according to the firstindication information and perform data transmission with the targetcell. If there are two or more second cells in the coverage of the firstbase station, the terminal may receive system information transmitted byeach second cell in the at least one second cell on the second frequencyband according to the second frequency band indicated by the firstindication information. The terminal may determine one or more secondcells in the at least one second cell to be the target cell(s) accordingto the cell selection or cell reselection rule. A method by which theterminal determines the target cell(s) according to the cell selectionor cell reselection rule may be implemented through the prior art.Detailed descriptions about a specific process by which the terminaldetermines the target cell(s) are omitted herein for simplicity.

It is to be understood that the terminal may select the one or moresecond cells to be the target cell(s) on the second frequency bandaccording to the cell selection or cell reselection rule. There are nospecial limits made to the number of the target cell(s) in thedisclosure.

In the embodiment of the disclosure, the first indication informationbroadcast by the first base station may be paging information. Or, thefirst indication information broadcast by the first base station may bethe paging information and configuration information of the targetcell(s). Or, the first indication information may be system information.

Alternatively, the first indication information is the paginginformation transmitted by the first base station through the firstcell, or the first indication information is the paging information andconfiguration information of the target cell(s). The first indicationinformation includes information of a second frequency band and/orinformation of a base station (i.e., target base station) containing thetarget cell(s) and/or information of the target cell.

The information of the second frequency band includes at least one offrequency band information, bandwidth, a threshold value or an offset.The information of the base station of which the target cell includes atarget base station ID. The information of target cell includes at leastone of a cell ID or a cell access technology.

Alternatively, the operation in S204 that the terminal determines theone or more second cells using the second frequency band to be thetarget cell(s) according to the first indication information includesone of the following two actions.

The terminal determines the target cell(s) according to the paginginformation.

The terminal determines the target cell(s) according to the paginginformation and the configuration information of the target cell(s).

Specifically, a network side, when having downlink data to betransmitted to the terminal, may transmit a paging message to notify theterminal. For example, the paging message may directly be transmitted tothe first base station by a core network, and then the first basestation generates the paging information to be transmitted in the firstcell according to the paging message. Specifically, the first basestation may generate the first indication information according to thepaging message, the first indication information including theinformation of the second frequency band and/or information of the basestation (i.e., target base station) containing the target cell(s) and/orinformation of the target cell, and the first indication informationbeing transmitted in the first cell in form of the paging information.Or, the first base station adds the information of the second frequencyband and/or information of the base station (i.e., target base station)containing the target cell(s) and/or information of the target cell intothe paging information to be transmitted in the first cell. The firstbase station transmits the paging information in the first cell, toenable the terminal to determine the target cell(s) when receiving thepaging information and further transmit data with the target cell(s).

Furthermore, the first base station, after receiving the paging messagetransmitted by the core network, may further determine the configurationinformation of the target cell(s) according to a paging region, andgenerate the first indication information on the basis of the pagingmessage and the configuration information of the target cell(s). Theterminal, after receiving the first indication information, may look forthe target cell(s) in a smaller range according to the paginginformation and the configuration information of the target cell(s), andtransmit data with the target cell(s). For example, the paging regionindicated by the paging information is five second cells on the secondfrequency band, and the configuration information of the target cell(s)indicates that the target cell(s) is within a range of three secondcells in the five second cells. Therefore, the range where the terminallooks for the target cell(s) is narrowed, and the efficiency ofdetermining the target cell by the terminal may be improved.

Alternatively, the first indication information is the systeminformation of the second cell transmitted by the first base stationthrough the first cell. The system information includes the informationof the second frequency band and/or information of the base station(i.e., second base station) containing the second cell and/orinformation of the second cell.

The operation in S202 that the terminal receives the first indicationinformation in the first cell using the first frequency band when nodata is to be transmitted or received includes that, the terminalreceives system information of at least one second cell in the firstcell using the first frequency band, the system information of the atleast one second cell corresponding to the at least one second cell.

The second frequency band information includes at least one of thefrequency band information, the bandwidth, the threshold value or theoffset. The corresponding base station information of the second cellincludes a second base station ID. The second cell information includesat least one of a cell ID or a cell access technology. It is to beunderstood that specific contents of the second frequency bandinformation, the corresponding base station information of the cells(including the target cell(s) and the second cell) and the cell(including the target cell(s) and the second cell) information arelisted above only for exemplary description and should not form anylimit to the disclosure. The disclosure is also not limited thereto.

Alternatively, the operation in S204 that the terminal determines theone or more second cells using the second frequency band to be thetarget cell(s) according to the first indication information includesthat, the terminal determines one or more second cells in the at leastone second cell to be the target cell(s) according to the systeminformation of the at least one second cell.

The terminal determines the one or more second cells from the at leastone second cell to be the target cell(s) according to the systeminformation of the at least one second cell on the basis of the cellselection or cell reselection rule.

Exemplarily but unlimitedly, the access technology includes an LTEtechnology, Wireless-Fidelity (Wi-Fi), a UTMS technology or a5th-Generation (5G) mobile communication technology.

It is to be understood that the access technology is listed above onlyfor exemplary description and should not form any limit to thedisclosure. The disclosure is also not limited thereto. The terminal mayalso communicate through another existing access technology or anotherfuture access technology.

In S206, the terminal performs cell synchronization with the target,cell(s).

Specifically, before the operation that the terminal performs datatransmission in the second cell using the second frequency bandaccording to the first indication information when there is data to betransmitted, the method 200 further includes that, the terminal performscell synchronization with the target cell(s) according to the firstindication information.

Synchronization between the terminal and the target cell(s) may beclassified into downlink synchronization and uplink synchronization.

At first, the terminal performs downlink synchronization with the targetcell(s). In the embodiment of the disclosure, the terminal may directlyreceive a downlink synchronization signal (denoted as a target downlinksynchronization signal for convenience of distinction and description)periodically broadcast by the target base station on the secondfrequency band for downlink synchronization with the target cell(s), andmay also receive downlink synchronization information of the targetcell(s) transmitted by the first base station on the first frequencyband and perform downlink synchronization with the target cell(s)according to the downlink synchronization information. A specificprocess of downlink synchronization between the terminal and the targetcell(s) will be described below in detail.

In an implementation mode, the operation that the terminal performsdownlink synchronization with the target cell(s) specifically includesthe following operations. The terminal receives at least one downlinksynchronization signal transmitted by at least one second base stationon the second frequency band according to the first indicationinformation. The at least one downlink synchronization signalcorresponds to the at least one second base station. Each downlinksynchronization signal is from the corresponding second base station.

The terminal determines the downlink synchronization signals of thetarget cell(s) from the at least one downlink synchronization signal.

The terminal performs downlink synchronization with the target cell(s)according to the downlink synchronization signals of the target cell(s).

Specifically, each second base station (including the target basestation) may periodically broadcast the downlink synchronization signalof each second cell on the second frequency band, for example, PrimarySynchronization Signals (PSSs) and Secondary Synchronization Signals(SSSs).

If there is only one second cell on the second frequency band, thesecond cell is a target cell of the terminal. The terminal, afterreceiving a PSS and SSS broadcast by a base station (i.e., a second basestation or a target base station) of the second cell on the secondfrequency band, completes frame synchronization and acquires a cell IDof the cell (i.e., the target cell) corresponding to the downlinksynchronization signals, thereby completing downlink synchronization ofthe terminal and the target cell.

If there are multiple second cells on the second frequency band, a basestation of each second cell may periodically broadcast a downlinksynchronization signal (denoted as a second downlink synchronizationsignal for convenience of distinction and description) of the respectivecell. The second downlink synchronization signal includes a downlinksynchronization signal of a target cell. The terminal, when receivingthe second downlink synchronization signals of the multiple second cellson the second frequency band, may determine the downlink synchronizationsignal of the target cell according to a cell ID of each second cellcorresponding to the second downlink synchronization signal of thesecond cell, and a cell ID of the target cell indicated by the firstindication information or the cell ID of the target cell determinedthrough cell selection or cell reselection, and complete downlinksynchronization with the target cell.

In another implementation mode, the operation that the terminal performsdownlink synchronization with the target cell(s) specifically includesthe following actions.

The terminal receives downlink synchronization information of the firstcell in the first cell.

The terminal determines downlink synchronization information of thetarget cell(s).

The terminal performs downlink synchronization with the target cell(s)according to the downlink synchronization information of the targetcell(s).

The operation that the terminal determines the downlink synchronizationinformation of the target cell(s) includes the following actions.

The terminal receives at least one downlink synchronization offsetinformation from the first base station through the first cell andcorresponding to the at least one second cell, each downlinksynchronization offset information including a time offset betweentiming of the corresponding second cell and timing of the first cell andthe first base station being the base station containing the first cell.

The terminal determines the downlink synchronization information of thetarget cell(s) according to the downlink synchronization offsetinformation of the at least one second cell.

Specifically, the terminal may receive the downlink synchronizationinformation of the first cell from the first base station, the downlinksynchronization information of the first cell indicating a time offsetbetween timing of the terminal and the first cell. The terminal mayfurther determine the downlink synchronization information of the targetcell(s) the downlink synchronization information of the target cell(s)indicating (a) time offset(s) between timing of the first cell and thesecond cell(s).

The terminal may determine the downlink synchronization information ofthe target cell(s) according to pre-stored time offsets between basestations. For example, the terminal knows that the time offset betweenthe base stations is 2 ms.

The terminal may also determine the downlink synchronization informationof the target cell(s) according to downlink synchronization informationof the second cell transmitted by the first base station. Specifically,the first base station transmits at least one downlink synchronizationinformation corresponding to the at least one second cell to theterminal, each downlink synchronization information including the timeoffset between the timing of the corresponding second cell and the firstcell. The terminal may determine the time offsets of the target cell(s)according to the determined cell information of the target cell(s).

The terminal, after completing downlink synchronization with the targetcell(s), may further perform uplink synchronization with the targetcell(s).

Alternatively, the operation that the terminal performs uplinksynchronization with the target cell(s) specifically includes thefollowing actions.

The terminal transmits an uplink synchronization request to the targetbase station containing the target cell(s) on the second frequency band.The uplink synchronization request is configured to obtain the uplinksynchronization information of the terminal and the target cell(s).

The terminal receives uplink synchronization information in the firstcell. The uplink synchronization information is acquired by the firstbase station from the target base station, the uplink synchronizationinformation is determined by the target base station on the basis of theuplink synchronization request and the uplink synchronizationinformation indicating a time offset between timing of the terminal andthe base station.

The terminal performs uplink synchronization with the target cell(s)according to the uplink synchronization information.

The uplink synchronization request or a transmitting resource (forexample, a time-frequency resource) is determined by the target basestation and transmitted to the terminal through the first base station.

Uplink synchronization request information is transmitted to theterminal by the first base station, after the target base stationreceives the uplink synchronization request from the terminal,acknowledges the uplink synchronization request, and allocates thetransmitting resource.

The uplink synchronization request information includes indicationinformation of the transmitting resource.

Specifically, the terminal, before transmitting the uplinksynchronization request to the target base station on the secondfrequency band, is required to know the time-frequency resource fortransmitting the uplink synchronization request. The time-frequencyresource may be requested by the first base station from the target basestation. Specifically, the first base station determines thetime-frequency resource, and then transmits the request for thetime-frequency resource to the target base station, the target basestation specifies the time-frequency resource, and then the first basestation transmits the indication information of the time-frequencyresource to the terminal. The time-frequency resource may also bedirectly determined by the target base station and the indicationinformation of the time-frequency resource is transmitted to theterminal by the first base station. The terminal, after receiving theindication information of the time-frequency resource, may transmit theuplink synchronization request to the target base station on thespecified time-frequency resource. Or, the terminal transmits a RandomAccess (RA) request to the target base station on the second frequencyband. The uplink synchronization request may include a random accesspreamble. The target base station, after receiving the uplinksynchronization signal, may determine the uplink synchronizationinformation according to the received uplink synchronization request.The uplink synchronization signal indicates the timing of the terminal,and the uplink synchronization information indicates the time offsetbetween the timing of the terminal and the timing of the target basestation. Alternatively, the time offset may be an uplink transmittingTime Alignment (TA). The terminal, after receiving the uplinksynchronization information, may regulate uplink transmitting timeaccording to the time offset to complete uplink synchronization with thetarget cell(s). Or, the terminal completes uplink synchronization forthe target cell(s).

In the embodiment of the disclosure, the uplink synchronizationinformation to be transmitted to the terminal by the target base stationmay be forwarded through the first base station. That is, the terminalreceives the uplink synchronization information of the target cell(s)from the first base station on the first frequency band, and the uplinksynchronization information of the target cell(s) is acquired by thefirst base station from the target base station.

Therefore, the terminal completes uplink and downlink synchronizationwith the target cell(s). In the embodiment of the disclosure, forreducing relatively high power consumption probably brought by receptionof the downlink control signaling by the terminal camping on the targetcell(s), the terminal may be controlled to, when there is no datatransmission, keep synchronized with the low-frequency cell (forexample, the first cell) and the target cell(s), and receive thedownlink control signaling of the target cell(s) in the low-frequencycell and, when there is data to be transmitted, transmit data with thetarget base station.

In S208, when there is data to be transmitted, the terminal performsdata transmission with the target cell(s) using the second frequencyband.

Specifically, data transmission of the terminal includes uplink datatransmission and downlink data transmission.

When the terminal has uplink data to be transmitted, the terminal maydirectly transmit data to the target cell(s) according to the receivedsystem information of the target cell(s). When the network side hasdownlink data to be transmitted to the terminal, the paging informationmay be transmitted firstly to enable the terminal to access the targetcell(s) or transmit data with the target cell(s) according to the paginginformation.

When there is uplink data to be transmitted, the first indicationinformation is the system information of each second cell. The firstbase station may acquire the system information of each second cell fromthe serving base station (i.e., the second base station) of the secondcell, or may pre-store the system information of each second cell. Thefirst base station may periodically broadcast the system information ofeach second cell. The terminal may determine the system information ofthe target cell(s) according to the received system information of eachsecond cell and the cell IDs of the target cell(s) determined by theterminal and transmit data with the target base station according to thesystem information of the target cell(s).

When there is downlink data to be transmitted, the first indicationinformation is the paging information, or the first indicationinformation is the paging information and the configuration informationof the target cell(s). The terminal may directly determine the targetcell(s) according to the first indication information and transmit datawith the target base station.

In such a manner, according to the data transmission method of theembodiment of the disclosure, the terminal completes synchronizationwith a target cell in advance on the first frequency band and, whenthere is data to be transmitted, performs data transmission with thetarget cell, so that relatively high power consumption probably broughtby reception of downlink control signaling by the terminal camping on ahigh frequency band is avoided. Meanwhile, synchronization with thetarget cell is completed in advance to make it possible to access ahigh-frequency-band cell as fast as possible or implement datatransmission with the target cell when there is data to be transmitted.Compared with the prior art, the method greatly reduces the cell accessflow in the prior art and reduces a signaling overhead.

The data transmission method according to the embodiments of thedisclosure has been described above in combination with FIG. 2 indetail. A data transmission device according to the embodiments of thedisclosure will be described below in combination with FIG. 3 to FIG. 5in detail.

FIG. 3 illustrates a schematic block diagram of a terminal 300 accordingto an embodiment of the disclosure. As illustrated in FIG. 3, theterminal 300 includes a transceiver unit 310.

The transceiver unit 310 is configured to, when no data is to betransmitted or received, receive first indication information in a firstcell using a first frequency band, the first indication informationbeing configured to instruct the terminal receiving the first indicationinformation to perform data transmission using a second frequency bandwhen there is data to be transmitted.

The transceiver unit 310 is further configured to, when there is data tobe transmitted, perform data transmission in a second cell using thesecond frequency band according to the first indication information.

Alternatively, the terminal 300 further includes a determination unitand a processing unit.

The determination unit is configured to determine one or more secondcells using the second frequency band to be (a) target cell(s) accordingto the first indication information.

The processing unit is configured to perform cell synchronization withthe target cell(s).

The transceiver unit 310 is specifically configured to, when there isdata to be transmitted, perform data transmission with the targetcell(s) using the second frequency band.

Alternatively, the first indication information is paging informationtransmitted by a first base station through the first cell, or the firstindication information is paging information and configurationinformation of the target cell(s). The first indication informationincludes information of a second frequency band and/or information of abase station (i.e., target base station) containing the target cell(s)and/or information of the target cell. The first base station is a basestation containing the first cell.

The determination unit is specifically configured to determine thetarget cell(s) according to the paging information.

Or, the determination unit is specifically configured to determine thetarget cell(s) according to the paging information and the configurationinformation of the target cell(s).

Alternatively, the first indication information is system information ofthe second cell transmitted by the first base station through the firstcell. The system information of the second cell includes the informationof the frequency band of the second cell and/or information of the basestation (i.e., second base station) containing the second cell and/orinformation of the second cell. The first base station is the basestation containing the first cell.

The transceiver unit 310 is specifically configured to receive systeminformation of at least one second cell in the first cell using thefirst frequency band. The system information of the at least one secondcell corresponds to the at least one second'cell.

The determination unit is specifically configured to determine one ormore second cells from the at least one second cell to be (a) targetcell(s) according to the system information of the at least one secondcell.

Alternatively, the transceiver unit 310 is further configured totransmit an uplink synchronization request to a target base stationcontaining the target cell(s) on the second frequency band. The uplinksynchronization request is configured to obtain uplink synchronizationinformation between the terminal and the target cell(s).

The transceiver unit 310 is further configured to receive the uplinksynchronization information in the first cell. The uplinksynchronization information is acquired by the first base station fromthe target base station, the uplink synchronization information isdetermined by the target base station on the basis of the uplinksynchronization request, and the first base station is the base stationcontaining the first cell.

The processing unit is specifically configured to perform uplinksynchronization with the target cell(s) according to the uplinksynchronization information.

Alternatively, the transceiver unit 310 is further configured to receivedownlink synchronization information of the first cell in the firstcell.

The determination unit is further configured to determine downlinksynchronization information of the target cell(s).

The processing unit is specifically configured to perform downlinksynchronization with the target cell(s) according to the downlinksynchronization information of the target cell(s).

Alternatively, the transceiver unit 310 is further configured to receiveat least one downlink synchronization offset information transmitted bythe first base station through the first cell and corresponding to theat least one second cell. Each downlink synchronization offsetinformation includes a time offset between timing of the correspondingsecond cell and timing of the first cell, and the first base station isthe base station containing the first cell.

The determination unit is specifically configured to determine thedownlink synchronization information of the target cell(s) according tothe downlink synchronization offset information of the at least onesecond cell.

The terminal 300 according to the embodiment of the disclosure maycorrespond to a terminal in the data transmission method of theembodiments of the disclosure. Moreover, each unit in the terminal 300and the other abovementioned operations and/or functions are adopted toimplement the corresponding flows of the method in FIG. 2 respectivelyand will not be elaborated herein for simplicity.

In such a manner, the terminal according to the embodiment of thedisclosure completes synchronization with a target cell in advance onthe first frequency band and, when there is data to be transmitted,performs data transmission with the target cell, so that relatively highpower consumption probably brought by reception of downlink controlsignaling by the terminal camping on a high frequency band is avoided.Meanwhile, synchronization with the target cell is completed in advanceto make it possible to implement data transmission with the target cellwhen there is data to be transmitted. Compared with the prior art, theterminal according to the embodiment of the disclosure greatly reducescell access process in the prior art and reduces a signaling overhead.

FIG. 4 illustrates a schematic block diagram of a base station 400according to an embodiment of the disclosure. As illustrated in FIG. 4,the base station 400 includes a determination unit 410 and a transceiverunit 420.

The determination unit 410 is configured to determine first indicationinformation. The first indication information is configured to instructa terminal receiving the first indication information to transmit datain a second cell using a second frequency band. The base station is abase station containing a first cell using a first frequency band.

The transceiver unit 420 is configured to transmit the first indicationinformation through the first cell.

Alternatively, the first indication information is paging information orpaging information and configuration information of a target cell. Thefirst indication information includes information of a second frequencyband and/or information of a base station (i.e., target base station)containing the target cell(s) and/or information of the target cell. Thesecond cell includes the target cell. A target base station is a basestation containing the target cell.

The transceiver unit 420 is specifically configured to transmit thepaging information through the first cell.

Or, the transceiver unit 420 is specifically configured to transmit thepaging information and the configuration information of the target cellthrough the first cell.

Alternatively, the first indication information is system information ofthe second cell. The system information of the second cell includesinformation of the frequency band of the second cell and/or informationof a base station containing the second cell and/or information of thesecond cell.

The transceiver unit 420 is further configured to receive systeminformation of at least one second cell, transmitted by at least onesecond base station, the system information of the at least one secondcell corresponding to the at least one second cell.

The transceiver unit 420 is specifically configured to transmit thesystem information of the at least one second cell through the firstcell.

Alternatively, the transceiver unit 420 is further configured totransmit uplink synchronization information through the first cell. Theuplink synchronization information is acquired by the base station fromthe target base station, and the uplink synchronization information isdetermined by the target base station on the basis of an uplinksynchronization request transmitted to the target base station by theterminal on the second frequency band. The target base station is thebase station containing the target cell. The target cell is determinedby the terminal from the at least one second cell.

Alternatively, the transceiver unit 420 is further configured totransmit downlink synchronization information of the first cell to theterminal through the first cell.

Alternatively, the transceiver unit 420 is further configured totransmit at least one downlink synchronization offset informationcorresponding to the at least one second cell to the terminal throughthe first cell. Each downlink synchronization offset informationincludes a time offset between timing of the corresponding second celland timing of the first cell.

The base station 400 according to the embodiment of the disclosure maycorrespond to a first base station in the data transmission method ofthe embodiments of the disclosure. Moreover, each unit in the basestation 400 and the other abovementioned operations and/or functions areadopted to implement the corresponding flows of the method in FIG. 2respectively and will not be elaborated herein for simplicity.

In such a manner, the base station according to the embodiment of thedisclosure transmits downlink control signaling to the terminal on thefirst frequency band, to enable the terminal to complete synchronizationwith a target cell in advance on the first frequency band, and whenthere is data to be transmitted, the terminal may perform datatransmission with the target cell, so that relatively high powerconsumption probably brought by reception of downlink control signalingby the terminal camping on a high frequency band is avoided. Meanwhile,synchronization with the target cell is completed in advance to make itpossible to implement data transmission with the target cell when thereis data to be transmitted. Compared with a prior art, the base stationaccording to the embodiment of the disclosure greatly reduces cellaccess process in the prior art and reduces a signaling overhead.

FIG. 5 illustrates a schematic block diagram of another base station 500according to another embodiment of the disclosure. As illustrated inFIG. 5, the base station 500 includes a transceiver unit 510.

The transceiver unit 510 is configured to transmit system information ofa second cell to a first base station. The system information isconfigured to indicate a system parameter of the second cell, a carrierfrequency corresponding to the second cell belongs to a second frequencyband, the first base station is a base station containing a first cellusing a first frequency band and the second base station pre-stores amapping relationship between the second cell and the first cell.

The transceiver unit 510 is further configured to transmit data with aterminal through the second cell.

Alternatively, the transceiver unit 510 is further configured to receivean uplink synchronization request transmitted by the terminal on thesecond frequency band. The uplink synchronization request is configuredto obtain uplink synchronization information of the terminal and thesecond cell.

The transceiver unit 510 is further configured to determine the uplinksynchronization information according to the uplink synchronizationrequest and transmit the uplink synchronization information to the firstbase station.

The base station 500 according to the embodiment of the disclosure maycorrespond to a second base station in the data transmission method ofthe embodiments of the disclosure. Moreover, each unit in the basestation 500 and the other abovementioned operations and/or functions areadopted to implement the corresponding flows of the method in FIG. 2respectively and will not be elaborated herein for simplicity.

In such a manner, according to the base station of the embodiment of thedisclosure, the terminal in the first cell completes synchronizationwith the target cell in advance, and when there is data to betransmitted, data transmission is performed with the terminal, so thatrelatively high power consumption probably brought by reception ofdownlink control signaling by the terminal camping on a high frequencyband is avoided. Meanwhile, synchronization with the target cell iscompleted in advance to make it possible to implement data transmissionwith the target cell when there is data to be transmitted. Compared withthe prior art, the base station of the embodiment of the disclosuregreatly reduces cell access process in the prior art and reduces asignaling overhead.

The data transmission device according to the embodiments of thedisclosure has been described above in combination with FIG. 3 to FIG. 5in detail. A data transmission device according to the embodiments ofthe disclosure will be described below in combination with FIG. 6 toFIG. 8 in detail.

FIG. 6 illustrates a schematic block diagram of a terminal 600 accordingto an embodiment of the disclosure. As illustrated in FIG. 6, theterminal 600 includes a transceiver 610, a processor 620, a memory 630and a bus system 640. The processor 620, the memory 630 and thetransceiver 610 are connected through the bus system 640. The memory 630is configured to store instructions. The processor 620 is configured toexecute the instructions stored in the memory 630 to control thetransceiver 610 to transmit and receive information.

The transceiver 610 is configured to, when no data is to be transmittedor received, receive first indication information in a first cell usinga first frequency band. The first indication information is configuredto instruct the terminal receiving the first indication information toperform data transmission using a second frequency band when there isdata to be transmitted.

The transceiver 610 is further configured to, when there is data to betransmitted, perform data transmission in a second cell using the secondfrequency band according to the first indication information.

It is to be understood that, in the embodiment of the disclosure, theprocessor 620 may be a Central Processing Unit (CPU), or the processor620 may be another universal processor, a Digital Signal Processor(DSP), an Application Specific Integrated Circuit (ASIC), aField-Programmable Gate Array (FPGA) or another programmable logicdevice, discrete gate or transistor logic device and discrete hardwarecomponent and the like. The universal processor may be a microprocessoror the processor may also be any conventional processor and the like.

The memory 630 may include a Read-Only Memory (ROM) and a Random AccessMemory (RAM) and provides an instruction and data for the processor 620.A part of the memory 630 may further include a nonvolatile RAM. Forexample, the memory 630 may further store information of a device type.

The bus system 640 includes a data bus, and may further include a powerbus, a control bus, a state signal bus and the like. However, for cleardescription, various buses in the figure are marked as the bus system640.

In an implementation process, each action of the method may be completedby an integrated logic circuit of hardware in the processor 620 orinstructions in a software form. The actions of a supercell handovermethod disclosed in combination with the embodiments of the disclosuremay be directly embodied to be executed and completed by a hardwareprocessor or executed and completed by a combination of hardware andsoftware modules in the processor. The software module may be located ina mature storage medium in this field such as a RAM, a flash memory, aROM, a programmable ROM or electrically erasable programmable ROM and aregister. The storage medium is located in the memory 630. The processor620 reads information in the memory 630 and completes the actions of themethod in combination with hardware. No more detailed descriptions willbe made herein to avoid repetitions.

Alternatively, the processor 620 is configured to determine one or moresecond cells using the second frequency band to be (a) target cell(s)according to the first indication information.

The processor 620 is further configured to perform cell synchronizationwith the target cell(s).

The transceiver 610 is specifically configured to, when there is data tobe transmitted, perform data transmission with the target cell(s) usingthe second frequency band.

Alternatively, the first indication information is paging information,or the first indication information is paging information andconfiguration information of the target cell(s) transmitted by a firstbase station through the first cell. The first indication informationincludes information of a second frequency band and/or information of abase station containing the target cell(s) and/or information of thetarget cell. The first base station is a base station containing thefirst cell.

The processor 620 is specifically configured to determine the targetcell(s) according to the paging information.

Or, the processor 620 is specifically configured to determine the targetcell(s) according to the paging information and the configurationinformation of the target cell(s).

Alternatively, the first indication information is system information ofthe second cell transmitted by the first base station through the firstcell. The system information of the second cell includes information ofthe frequency band of the second cell and/or information of the basestation containing the second cell and/or information of the secondcell. The first base station is the base station containing the firstcell.

The transceiver 610 is specifically configured to receive systeminformation of at least one second cell in the first cell using thefirst frequency band. The system information of the at least one secondcell correspond to the at least one second cell.

The processor 620 is specifically configured to determine one or moresecond cells from the at least one second cell to be (a) target cell(s)according to the system information of the at least one second cell.

Alternatively, the transceiver 610 is further configured to transmit anuplink synchronization request to a target base station containing thetarget cell(s) on the second frequency band. The uplink synchronizationrequest is configured to obtain uplink synchronization information ofthe terminal and the target cell(s).

The transceiver 610 is further configured to receive the uplinksynchronization information in the first cell. The uplinksynchronization information is acquired by the first base station fromthe target base station, the uplink synchronization information isdetermined by the target base station on the basis of the uplinksynchronization request, and the first base station is the base stationcontaining the first cell.

The processor 620 is specifically configured to perform uplinksynchronization with the target cell(s) according to the uplinksynchronization information.

Alternatively, the transceiver 610 is further configured to receivedownlink synchronization information of the first cell in the firstcell.

The processor 620 is further configured to determine downlinksynchronization information of the target cell(s).

The processor 620 is specifically configured to perform downlinksynchronization with the target cell(s) according to the downlinksynchronization information of the target cell(s).

Alternatively, the transceiver 610 is further configured to receive atleast one downlink synchronization offset information transmitted by thefirst base station through the first cell and corresponding to the atleast one second cell. Each downlink synchronization offset informationincludes a time offset between timing of the corresponding second celland timing of the first cell, and the first base station is the basestation containing the first cell.

The processor 620 is specifically configured to determine the downlinksynchronization information of the target cell(s) according to thedownlink synchronization offset information of the at least one secondcell.

The terminal 600 according to the embodiment of the disclosure maycorrespond to the terminal in the data transmission method of theembodiments of the disclosure. Moreover, each module in the terminal 600and the other abovementioned operations and/or functions are adopted toimplement the corresponding flows of the method in FIG. 2 respectivelyand will not be elaborated herein for simplicity.

In such a manner, the terminal according to the embodiment of thedisclosure completes synchronization with a target cell in advance onthe first frequency band and, when there is data to be transmitted orreceived, performs data transmission with the target cell, so thatrelatively high power consumption probably brought by reception ofdownlink control signaling by the terminal camping on a high frequencyband is avoided. Meanwhile, synchronization with the target cell iscompleted in advance to make it possible to implement data transmissionwith the target cell when there is data to be transmitted. Compared withthe prior art, the terminal according to the embodiment of thedisclosure greatly reduces cell access process in the prior art andreduces a signaling overhead.

FIG. 7 illustrates a schematic block diagram of a base station 700according to an embodiment of the disclosure. As illustrated in FIG. 7,the base station 700 includes a transceiver 710, a processor 720, amemory 730 and a bus system 740. The processor 720, the memory 730 andthe transceiver 710 are connected through the bus system 740. The memory730 is configured to store instructions. The processor 720 is configuredto execute the instructions stored in the memory 730 to control thetransceiver 710 to transmit and receive information.

The processor 720 is configured to determine first indicationinformation, the first indication information being configured toinstruct a terminal receiving the first indication information totransmit data in a second cell using a second frequency band, and thebase station is a base station containing a first cell using a firstfrequency band.

The transceiver 710 is configured to transmit the first indicationinformation through the first cell.

Alternatively, the first indication information is paging information,or the first indication information is paging information andconfiguration information of a target cell. The first indicationinformation includes information of a second frequency band and/orinformation of a base station containing the target cell(s) and/orinformation of the target cell. The second cell includes the targetcell. A target base station is a base station containing the targetcell.

The transceiver 710 is specifically configured to transmit the paginginformation through the first cell.

The transceiver 710 is specifically configured to transmit the paginginformation and the configuration information of the target cell throughthe first cell.

Alternatively, the first indication information is system information ofthe second cell. The system information of the second cell includesinformation of the frequency band of the second cell and/or informationof the base station containing the second cell and/or information of thesecond cell.

The transceiver 710 is further configured to receive system informationof at least one second cell transmitted by at least one second basestation. The system information of the at least one second cellcorresponds to the at least one second cell.

The transceiver 710 is specifically configured to transmit the systeminformation of the at least one second cell through the first cell.

Alternatively, the transceiver 710 is further configured to transmituplink synchronization information through the first cell. The uplinksynchronization information is acquired by the base station from thetarget base station, and the uplink synchronization information isdetermined by the target base station on the basis of an uplinksynchronization request transmitted to the target base station by theterminal on the second frequency band. The target base station is thebase station containing the target cell. The target cell is determinedby the terminal from the at least one second cell.

Alternatively, the transceiver 710 is further configured to transmitdownlink synchronization information of the first cell to the terminalthrough the first cell.

Alternatively, the transceiver 710 is further configured to transmit atleast one downlink synchronization offset information corresponding tothe at least one second cell to the terminal through the first cell.Each downlink synchronization offset information includes a time offsetbetween timing of the corresponding second cell and timing of the firstcell.

The base station 700 according to the embodiment of the disclosure maycorrespond to the first base station in the data transmission method ofthe embodiments of the disclosure. Moreover, each module in the basestation 700 and the other abovementioned operations and/or functions areadopted to implement the corresponding flows of the method in FIG. 2respectively and will not be elaborated herein for simplicity.

In such a manner, the base station according to the embodiment of thedisclosure transmits downlink control signaling to the terminal on thefirst frequency band, to enable the terminal to complete synchronizationwith a target cell in advance on the first frequency band and, whenthere is data to be transmitted, the terminal may perform datatransmission with the target cell, so that relatively high powerconsumption probably brought by reception of downlink control signalingby the terminal camping on a high frequency band is avoided. Meanwhile,synchronization with the target cell is completed in advance to make itpossible to implement data transmission with the target cell when thereis data to be transmitted. Compared with the prior art, the base stationaccording to the embodiment of the disclosure greatly reduces cellaccess process in the prior art and reduces a signaling overhead.

FIG. 8 illustrates a schematic block diagram of another base station 800according to another embodiment of the disclosure. As illustrated inFIG. 8, the base station 800 includes a transceiver 810, a processor820, a memory 830 and a bus system 840. The processor 820, the memory830 and the transceiver 810 are connected through the bus system 840.The memory 830 is configured to store instructions. The processor 820 isconfigured to execute the instructions stored in the memory 830 tocontrol the transceiver 810 to transmit and receive information.

The transceiver 810 is configured to transmit system information of asecond cell to a first base station. The system information isconfigured to indicate a system parameter of the second cell. A carrierfrequency corresponding to the second cell belongs to a second frequencyband, the first base station is a base station containing a first cellusing a first frequency band, and the second base station pre-stores amapping relationship between the second cell and the first cell.

The transceiver 810 is further configured to transmit data with aterminal through the second cell.

Alternatively, the transceiver 810 is further configured to receive anuplink synchronization request transmitted by the terminal on the secondfrequency band. The uplink synchronization request is configured toobtain uplink synchronization information between the terminal and thesecond cell.

The transceiver 810 is further configured to determine the uplinksynchronization information according to the uplink synchronizationrequest and transmit the uplink synchronization information to the firstbase station.

The base station 800 according to the embodiment of the disclosure maycorrespond to a second base station in the data transmission method ofthe embodiments of the disclosure. Moreover, each module in the basestation 800 and the other abovementioned operations and/or functions areadopted to implement the corresponding flow of the method in FIG. 2respectively and will not be elaborated herein for simplicity.

In such a manner, according to the base station of the embodiment of thedisclosure, the terminal in the first cell completes synchronizationwith the target cell in advance and, when there is data to betransmitted, data transmission is performed with the terminal, so thatrelatively high power consumption probably brought by reception ofdownlink control signaling by the terminal camping on a high frequencyband is avoided. Meanwhile, synchronization with the target cell iscompleted in advance to make it possible to implement data transmissionwith the target cell when there is data to be transmitted. Compared withthe prior art, the base station according to the embodiment of thedisclosure greatly reduces cell access process in the prior art andreduces a signaling overhead.

It is to be understood that term “and/or” in the disclosure is only anassociation relationship describing associated objects and representsthat three relationships may exist. For example, A and/or B mayrepresent three conditions: i.e., independent existence of A, existenceof both A and B and independent existence of B. In addition, character“/” in the disclosure usually represents that previous and nextassociated objects form an “or” relationship.

It is to be understood that, in various embodiments of the disclosure, amagnitude of a sequence number of each process does not mean anexecution sequence and the execution sequence of each process should bedetermined by its function and an internal logic and should not form anylimit to an implementation process of the embodiments of the disclosure.

Those of ordinary skill in the art may realize that the units andalgorithm actions of each example described in combination with theembodiments disclosed in the disclosure may be implemented by electronichardware or a combination of computer software and the electronichardware. Whether these functions are executed in a hardware or softwaremanner depends on specific applications and design constraints of thetechnical solutions. Professionals may realize the described functionsfor each specific application by use of different methods, but suchrealization shall fall within the scope of the disclosure.

Those skilled in the art may clearly learn about that specific workingprocesses of the system, device and unit described above may be seenfrom the corresponding processes in the method embodiment and will notbe elaborated herein for convenient and brief description.

In some embodiments provided by the disclosure, it is to be understoodthat the disclosed system, device and method may be implemented inanother manner. For example, the device embodiment described above isonly schematic, and for example, division of the units is only logicfunction division, and other division manners may be adopted duringpractical implementation. For example, multiple units or components maybe combined or integrated into another system, or some characteristicsmay be neglected executed. In addition, coupling or direct coupling orcommunication connection between each displayed or discussed componentmay be indirect coupling or communication connection, implementedthrough some interfaces, of the device or the units, and may beelectrical and mechanical or adopt other forms.

The units described as separate parts may or may not be physicallyseparated, and parts displayed as units may or may not be physicalunits, and namely may be located in the same place, or may also bedistributed to multiple network units. Part or all of the units may beselected to achieve the purpose of the solutions of the embodimentsaccording to a practical requirement.

In addition, each function unit in each embodiment of the disclosure maybe integrated into a processing unit, each unit may also existindependently, and two or more than two units may also be integratedinto a unit.

When being realized in form of software functional unit and sold or usedas an independent product, the function may also be stored in acomputer-readable storage medium. Based on such an understanding, thetechnical solutions of the disclosure substantially or parts makingcontributions to the prior art or part of the technical solutions may beembodied in form of software product, and the computer software productis stored in a storage medium, including a plurality of instructionsconfigured to enable a computer device (which may be a personalcomputer, a server, a network device or the like) to execute all or partof the actions of the method in each embodiment of the disclosure. Theabovementioned storage medium includes: various media capable of storingprogram codes such as a U disk, a mobile hard disk, a Read-Only Memory(ROM), a RAM, a magnetic disk or an optical disk.

The above is only the specific implementation mode of the disclosure andnot intended to limit the scope of protection of the disclosure. Anyvariations or replacements apparent to those skilled in the art withinthe technical scope disclosed by the disclosure shall fall within thescope of protection of the disclosure. Therefore, the scope ofprotection of the disclosure shall be subject to the scope of protectionof the claims.

1. A terminal, comprising: a transceiver, configured to, when no data isto be transmitted or received, receive first indication information in afirst cell using a first frequency band, the first indicationinformation being configured to instruct a terminal receiving the firstindication information to perform data transmission using a secondfrequency band when there is data to be transmitted or received, whereinthe transceiver is further configured to, when there is data to betransmitted or received, perform data transmission in a second cellusing the second frequency band according to the first indicationinformation.
 2. The terminal of claim 1, further comprising: aprocessor, configured to determine one or more second cells using thesecond frequency band to be a target cell according to the firstindication information; and the processor is configured to performsynchronization with the target cell, wherein the transceiver isconfigured to, when there is data to be transmitted or received, performdata transmission with the target cell using the second frequency band.3. The terminal of claim 2, wherein the first indication information ispaging information transmitted by a first base station through the firstcell, or the first indication information is the paging information andconfiguration information of the target cell, the first indicationinformation comprises at least one of the following information:information of a second frequency band, information of a base stationcontaining the target cell, or information of the target cell, the firstbase station is a base station containing the first cell, and theprocessor is configured to determine the target cell according to thepaging information; or, the processor is configured to determine thetarget cell according to the paging information and the configurationinformation of the target cell.
 4. The terminal of claim 2, wherein thefirst indication information is system information of the second celltransmitted by the first base station through the first cell, the systeminformation of the second cell comprises at least one of the followinginformation: information of a frequency band of the second cell,information of a base station containing the second cell, or informationof a second cell, and the first base station is a base stationcontaining the first cell, and the transceiver is configured to receivesystem information of at least one second cell, in the first cell usingthe first frequency band, the system information of the at least onesecond cell corresponding to the at least one second cell; and theprocessor is configured to determine one or more second cells from theat least one second cell to be the target cell according to the systeminformation of the at least one second cell.
 5. The terminal of claim 2,wherein the transceiver is further configured to transmit an uplinksynchronization message to the target cell belonging to a target basestation on the second frequency band, the uplink synchronization messagebeing configured to obtain uplink synchronization information betweenthe terminal and the target cell; the transceiver is further configuredto receive the uplink synchronization information in the first cell, theuplink synchronization information being acquired by the first basestation from the target base station, the uplink synchronizationinformation being determined by the target base station on the basis ofthe uplink synchronization message, and the first base station being thebase station containing the first cell; and the processor is configuredto perform uplink synchronization with the target cell according to theuplink synchronization information.
 6. The terminal of claim 5, whereinuplink synchronization information and a transmitting resource aredetermined by the target base station and transmitted to the terminalthrough the first base station; or the uplink synchronizationinformation is requested by the first base station from the target basestation, and transmitted to the terminal by the first base station afterthe target base station obtains the uplink synchronization informationand allocates the transmitting resource, wherein the uplinksynchronization information comprises indication information of thetransmitting resource.
 7. The terminal of claim 2, wherein thetransceiver is further configured to receive downlink synchronizationinformation of the first cell in the first cell; the processor isfurther configured to determine downlink synchronization information ofthe target cell; and the processor is configured to perform downlinksynchronization with the target cell according to the downlinksynchronization information of the target cell.
 8. The terminal of claim7, wherein the transceiver is further configured to receive at least onedownlink synchronization offset information transmitted by the firstbase station through the first cell and corresponding to the at leastone second cell, each downlink synchronization offset informationcomprising a time offset between timing of the corresponding second celland timing of the first cell, and the first base station being the basestation containing the first cell; and the processor is configured todetermine the downlink synchronization information of the target cellaccording to the downlink synchronization offset information of the atleast one second cell.
 9. A base station, comprising: a processor,configured to determine first indication information, the firstindication information being configured to indicate a terminal receivingthe first indication information to transmit data in a second cell usinga second frequency band, and the base station being a base stationcontaining a first cell using a first frequency band; and a transceiver,configured to transmit the first indication information through thefirst cell.
 10. The base station of claim 9, wherein the firstindication information is paging information, or the first indicationinformation is the paging information and configuration information of atarget cell, the first indication information comprises at least one ofthe following information: information of a second frequency band,information of a target base station, or information of the target cell,the second cell comprises the target cell, and the target base stationis a base station containing the target cell, and the transceiver isconfigured to transmit the paging information through the first cell;or, the transceiver is configured to transmit the paging information andthe configuration information of the target cell through the first cell.11. The base station of claim 9, wherein the first indicationinformation is system information of the second cell, the systeminformation of the second cell comprises at least one of the followinginformation: information of a frequency band of the second cell,information of a base station containing the second cell, or informationof the second cell, and the transceiver is further configured to receivesystem information of at least one second cell from at least one secondbase station, the system information of the at least one second cellcorresponding to the at least one second cell; and the transceiver isconfigured to transmit the system information of the at least one secondcell through the first cell.
 12. The base station of claim 9, whereinthe transceiver is further configured to transmit uplink synchronizationinformation through the first cell, the uplink synchronizationinformation being acquired by the first base station from the targetbase station, and the uplink synchronization information beingdetermined by the target base station on the basis of an uplinksynchronization message transmitted by the terminal to the target basestation on the second frequency band, wherein the target base station isa base station containing the target cell, and the target cell isdetermined by the terminal from the at least one second cell.
 13. Thebase station of claim 9, wherein the transceiver is further configuredto transmit downlink synchronization information of the first cell tothe terminal through the first cell.
 14. The base station of claim 13,wherein the transceiver is further configured to transmit at least onedownlink synchronization offset information corresponding to the atleast one second cell to the terminal through the first cell, eachdownlink synchronization offset information comprising a time offsetbetween timing of the corresponding second cell and timing of the firstcell.
 15. A base station, comprising: a transceiver, configured totransmit system information of a second cell to a first base station,the system information being configured to indicate a system parameterof the second cell, a carrier frequency corresponding to the second cellbelonging to a second frequency band, the first base station being abase station to which a first cell using a first frequency band belongsand the second base station pre-storing a mapping relationship betweenthe second cell and the first cell, wherein the transceiver is furtherconfigured to transmit data with a terminal through the second cell. 16.The base station of claim 15, wherein the transceiver is furtherconfigured to receive an uplink synchronization request from theterminal on the second frequency band, the uplink synchronizationrequest being configured to obtain uplink synchronization informationbetween the terminal and the second cell; and the transceiver is furtherconfigured to determine the uplink synchronization information accordingto the uplink synchronization request and transmit the uplinksynchronization information to the first base station.